Method for testing abrasion resistance of a test specimen

ABSTRACT

A method for testing abrasion resistance of a test specimen made of refractory material, wherein the method includes using an insulated furnace with a first chamber having a refractory lining, a second chamber disposed within the first chamber, a tube for flowing pressurized air into the second chamber, a conduit for flowing heated air from a burner operating on a fuel to the second chamber, for mixing with the pressurized air, and an air gun for mixing an abrading material into the pressurized air prior to introduction to the test specimen.

FIELD

The present embodiments generally relate to method for testing abrasionresistance of a test specimen.

BACKGROUND

A need exists for an method for testing abrasion resistance of a testspecimen by preheating a test specimen without preheating the abrasivematerial prior to introducing the abrasive material to the heated testspecimen to qualify material of test specimens and compare test specimenproperties.

The present embodiments meet this need.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description will be better understood in conjunction withthe accompanying drawings as follows:

FIG. 1 depicts a schematic of equipment usable with this novel method.

FIG. 2 is a top view of the entry ports of the insulated furnace.

FIG. 3 is a cross sectional view of an air gun with meter and funnelused in the method.

FIG. 4 is a diagram of the controller used in the method.

The present embodiments are detailed below with reference to the listedFigures.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Before explaining the present method in detail, it is to be understoodthat the method is not limited to the particular embodiments and that itcan be practiced or carried out in various ways.

The present embodiments relate to method for testing abrasion resistanceof a test specimen.

The embodiments can further relate to a method for testing abrasionresistance of a test specimen made of refractory material, wherein themethod includes using an insulated furnace with a first chamber having arefractory lining, a second chamber disposed within the first chamber, atube for flowing pressurized air into the second chamber, a conduit forflowing heated air from a burner operating on a fuel to the secondchamber, for mixing with the pressurized air, and an air gun for mixingan abrading material into the pressurized air prior to introduction tothe test specimen.

The benefit to this test is to be able to perform blast type abrasiontest at elevated temperatures. This test will allow for the comparisonof different material's abrasive resistance at a given temperature. Thiswill allow for the materials to be compared in side by side tests. Thistest method will also enable for a database to be generated for theproperties of different materials. This data base will allow differentbatches of materials to be compared to a standard generated by knowledgegained from this test. This test will also allow for the elevatedtemperature erosion resistance of different abrading media to becompared.

Turning now to the Figures, FIG. 1 shows equipment usable for the methodfor testing abrasion resistance of a test specimen 10 at elevatedtemperatures hereinafter referred to as test temperatures between about230 degrees Fahrenheit to about 2000 degrees Fahrenheit.

The test specimen can be a material capable of resisting deformation atelevated temperatures. The test specimen can be a refractory material, ametal, a ceramic, a ceramic and metal, a composite of ceramic and glass,a composite of ceramic and another material or combinations of these.

The test specimen can be a substrate, which can further have a coatingdisposed on the substrate, and the coating can be a material capable ofresisting deformation at an elevated temperature. If the test specimenis a coating, the coating can be a ceramic and metal coating or anothercomposite such as ceramic and metal. The coating can be between about ¼inch to about 1/100 inch in thickness.

The test can be initiated by determining a density of at least one testspecimen and a weight of the at least one test specimen

The test can be concluded by calculating a volume of lost material fromthe test specimen that occurred during a specified test duration. Thetest uses an abrading media striking the test specimen at a definedangle, such as at about 10 degrees to about 90 degrees, at a definedtemperature, such as between about 230 degrees Fahrenheit to about 2300degrees Fahrenheit for a specific duration of time such as from about 7minutes to about 2 hours, and possibly longer for certain types ofmaterial or if multiple types of abrading material need to be impactedon the test specimen.

These calculations can be made after the test specimen is removed fromthe furnace and weighed to determine weight loss using a known densitythereby determining a volume of loss of the test specimen.

The Figure depicts an insulated furnace 28 that can be a 3 foot by 3foot housing 25 or the housing can have another dimension. An example ofthis type of furnaces can be made by Robert J. Jenkins and Company ofHouston, Tex. The insulated furnace 28 can sustain temperatures betweenabout 100 degrees Fahrenheit to about 3000 degrees Fahrenheit.

In housing 25 of the insulated furnace 28 can be a first chamber 13. Thefirst chamber 13 can be lined with at least one refractory material 14a, however the first chamber can also be lined with two differentrefractory materials 14 a, and 14 b, shown in this Figure, which can belayered on top of each other or positioned adjacent each other dependingon the properties needed in the insulated furnace.

Examples of refractory material can be a ceramic or an insulatingmaterial capable of a low thermal conductivity between about 3 k toabout 10 k.

The lining of the first chamber can be a single lining of one refractorymaterial, or two layers forming one lining, where the first layer can bea first material and the second layer can be a second material, whichcan provide two different properties to the insulated furnace 28increasing the versatility of the furnace. The lining can be betweenabout 2 inches to about 8 inches in thickness.

From the top of the insulated furnace 28 and into the first chamber canextend inner wall 17 which can form a second chamber 15 within the firstchamber 13, which is also shown in this Figure. The inner wall 17 can bebetween about 0.5 inches to about 2 inches thick and can be made ofdense, erosion resistant material, such as refractory material,composite material or a metal. The inner wall can be round, or formed inthe shape of an angular octagon, hex, or a box.

Within the inner wall 17 can be a tube 46 that can extend from the topof the insulated furnace 28 to the second chamber 15. The tube 46 can bebetween about 8 inches to about 24 inches long and can be connected tothe top of the furnace using welds. The inner diameter of the tube 46can be between about ⅛th inches to about 1 inch. The tube can be taperedand be shaped from wider to narrower towards the test specimen.

The tube 46 can be made of steel, stainless steel or another materialthat resists deformation under the temperatures of the insulated furnace28. The tube 46 can extend from inside the insulated furnace 28 and canproject beyond the top of the insulated furnace 28 up to several inches.

The inner wall 17 can be a single continuous wall in an embodiment, in ashape that is other than round having an open end facing a test specimen10 that is on a substrate, such as a carrier 12 inside the first chamber13.

The carrier 12 can be a plurality of plates connected together orsupported in a set of parallel rails, which can enable multiple testspecimens to be tested sequentially.

Through the top of the insulated furnace 28 and providing an exit fromthe first chamber can be an exhaust port 20 for allowing air to exit theinsulated furnace 28. The exhaust port can have a diameter between about3 square inches to about 50 square inches.

The exhaust port can be flush with the top of the furnace and beclosable, such as with an exhaust valve, flap or similar device.

Through the top of the insulated furnace 28 is a first air intake 16which allows air to enter the second chamber 15 through the tube 46 thatis within the inner walls 17.

The exhaust port can be flush with the top of the furnace and can beclosable, such as with a valve, flap or similar device.

Through the top of the insulated furnace 28 can be a first air intake 16which can allow air to enter the second chamber 15 through the tube 46that is within the inner wall 17. The air of the first air intake 16 canbe maintained at a temperature below the test temperature.

The air of the first air intake 16 can be maintained at a temperaturebelow the test temperature.

The first air intake 16 can have a diameter greater than tube 46 and adiameter less than the second air intake 18.

The air of the first air intake 16 can be at a temperature near ambienttemperature, the second air intake 18 can be at a temperature above thetest temperature and above the first air intake 16, and the exhaust port20 can be at a temperature between the first and second temperatures.

The second air intake 18 can be through the top of the insulated furnace28 and can connect to the second chamber 15.

The air can enter the first chamber 13 through the second chamber 15surrounding the tube 46. The air entering through the second air intake18 can be maintained at a temperature above the test temperature whichis defined herein to be between about 230 degrees Fahrenheit to about2000 degrees Fahrenheit. The diameter of the second air intake 18 canrange between about 3 inches to about 10 inches.

Connected to the insulated furnace 28, shown in FIG. 1 as installed on aside of the insulated furnace 28 opposite the first chamber, can be acontroller 21. The controller 21 can have a processor, data storageconnected to the processor and computer instructions in the datastorage, which will be described later. The controller 21 can monitortemperature signals from the first and second and even thirdthermocouples and compare those signals with a predetermined limit indata storage and can further control the valve 38 that can restrict flowof a fuel 40 into the burner 42 that heat the air forming the heated air29. The fuel 40 can be natural gas, propane or a similar gaseous fuelwithout solid or liquid constituents.

The controller 21 can be connected through the walls of the insulatedfurnace with a wired connection, a wireless connection, or jointly in awired and wireless manner to at least three thermocouples, shown here asthermocouple 22, which is shown, adjacent the second air intake 18,second thermocouple 24 adjacent the test specimen, and thirdthermocouple 26 within the first chamber. The thermocouples can be thosesuch as the k thermocouple made by L and L Furnace. The thermocouplescan be used for monitoring air temperatures.

The controller 21 can be connected through the walls of the insulatedfurnace 28 or by a wireless connection, or jointly in a wired andwireless manner to a second thermocouple 24 for monitoring temperaturesat the test specimen.

The insulated furnace 28 further has a closable opening 27, such as adoor with a latch, for allowing at least one test specimen. Multipletest specimens to be placed in the insulated furnace for simultaneoustreatment and faster results using less energy.

FIG. 1 also shows a burner 42 connected to a fuel 40, which can furtherbe a fuel source, via a valve 38 such as a ball valve that can controlthe flow of a fuel to the burner 42. The burner can heat air formingheated air 29. The burner can be a burner such as the ones made byEclipse of Rockford, Ill.

The burner 42 can be connected to a blower 43, which can supply ambientair to the burner 42. The burner can flow the heated air 29 through aconduit 31 to the second air intake 18 at a rate of flow between about 3cubic feet per minute to about 45 cubic feet per minute.

The conduit 31 can be used for flowing heated air from a burneroperating on a fuel to the second chamber, for mixing with thepressurized air, and an air gun for mixing an abrading media into thepressurized air prior to introduction to the test specimen. Inadditional embodiments, multiple conduits can be used.

An air compressor 50 such as those made by Sullivan, can be in fluidcommunication with a unique and specially crafted air gun 52, through aregulator 78, for introducing pressurized air 44 to an air gun 52. Theair gun 52 can blend the pressurized air 44 with at least one abradingmedia 48 or 49. FIG. 1 shows two abrading medias being used in thesystem. The tube 46 can then carry the blended air 47 from the air gundown the tube, through the top of the insulated furnace 28 inside theinner wall 17 and out the tube inside the inner wall forming mixed air45 above the test specimen 10, wherein the mixed air is essentiallyblended air 47 mixed with the heated air 29 from the burner 42.

Additionally, at least one abrading media source 48 and an additionalabrading media source 49 can be connected to the air gun 52 for flowingabrading media into the pressurized air for introduction to theinsulated furnace for impacting the test specimen 10, which can be seenin more detail in FIG. 3.

The abrading media can be introduced through a meter 66 connected to apole 67. The pole 67 can hold the meter in alignment with a separatedfunnel 68 in this embodiment. The abrading media can flow from theseparated funnel to the air gun 52.

The abrading media can be a flowable particulate, with particulatediameters between about ⅛^(th) inches to about 20 microns. The abradingmedia can be a silicon carbide grit, a catalyst, particulate ofrefractory material, or combinations thereof.

A unique feature of this test, is that it can be a one pass test method,providing very specific sized particulate diameters.

In another embodiment the funnel can be connected to the meter 66 whichcan be fluidly connected to the abrading media.

The meter can be a fixed orifice or a valve meter, such as one made byRobert R. Jenkins and Company of Houston, Tex. The pole can be made ofmetal, such as stainless steel and have a diameter between about ¼inches to about 1 inches and can further be secured to a stand or footfor stability.

The meter and funnel can be disposed above the abrading media intakeport of the air gun to create the negative pressure needed prior toentering the chamber of the air gun 52. The air gun 52 can be a T-shapedconnection.

FIG. 1 also depicts a pressurized air gauge 76, which can monitorpressure of pressurized air 44 from the air compressor 50. A regulator78 can be disposed in line from the air compressor 50 to the air gun 52for controlling flow of pressurized air 44.

A negative pressure gauge 74 can be located between the separated funnel68 and the air gun 52 and can monitor negative pressure of abradingmedia entering the air gun, which can also be shown in more detail inFIG. 3.

An over temperature controller 70 can be connected to the controller 21and can provide emergency shut off of the insulated furnace 28 whentemperatures in the furnace exceed a predetermined limit.

An exhaust valve 80 can be disposed over the exhaust port 20 forregulating exhaust air from the insulated furnace.

FIG. 2 is a top view of the of the entry ports of the insulated furnace28. The Figure further shows the tube 46 for receiving the blended air47 through the first air intake 16. Second chamber 15 is depicted withthe inner wall 17 outside the second air intake 18.

FIG. 3 shows a cross sectional view of the air gun 52 that can receivethe pressurized air 44 through air inlet 58 and then into an air nozzle54 that can be secured to the body 56 that can flow into the chamber 64.

An abrading media intake port 62 can allow the abrading media 48, 49 toenter the air gun via the meter 66, through the funnel 68, which can belocated on pole 67, as shown in this Figure. The abrading media can thenmix with the pressurized air 44 in the chamber 64 before flowing outthrough the tube 46 and becoming blended air 47. An air outlet 60 isalso shown in the body 56 that can threadably engage the tube 46.

This Figure also shows the negative pressure gauge 74.

FIG. 4 shows the controller 21, which can have a processor 30 connectedto data storage 32 and further having computer instructions 34 insidedata storage. Also shown in this Figure, is display 72, which can beconnected to the processor 30 for displaying information from one ormore thermocouples. In this Figure, first thermocouple 22, secondthermocouple 24 and third thermocouple 36 are shown connected to thecontroller. The valve 38 and over temperature controller 70 can furtherbe connected to the controller.

Additional steps of this method can include equipment depicted inFIG. 1. Returning to FIG. 1, the steps and equipment can includemonitoring pressure of pressurized air 44 from the compressor with apressurized air gauge 76 and regulating flow of pressurized air 44 witha regulator 78 for controlling the flow of pressurized air 44.

Monitoring negative pressure caused by the relation of the tube 46 tothe air nozzle 54 of the air gun 52 using a negative pressure gauge 74for monitoring negative pressure.

Controlling operation of the insulated furnace 28 using an overtemperature controller 70 connected to the controller when temperaturesin the insulated furnace exceeds a predetermined limit.

Controlling air flow through the exhaust port using an exhaust valve 80disposed over the exhaust port 20.

In an embodiment, the method can be a continuous process that can testbetween about 2 test specimens to about 20 test specimens sequentially.

In an embodiment, a first test specimen can be impacted by a firstabrading media and a second test specimen can be impacted with a secondabrading media. The first and second abrading medias can be of the samemedia or can be different medias.

The abrading media can be accelerated in velocity from the first airintake through the tube to the test specimen by at least about 20percent from the initial velocity.

In an embodiment, the second chamber can have an inner wall that canextend at last 30 percent into the first chamber. The inner walls can bea tubular round or angular, such as octagonal.

While these embodiments have been described with emphasis on theembodiments, it should be understood that within the scope of theappended claims, the embodiments might be practiced other than asspecifically described herein.

1. A method for testing abrasion resistance of a test specimen atelevated temperatures of at least 230 degrees Fahrenheit comprising: a.determining a density of at least one test specimen and a weight of theat least one test specimen; b. placing the at least one test specimen ona carrier; c. placing the at least one test specimen on the carrier inan insulated furnace, wherein the insulated furnace comprises: i ahousing forming a first chamber lined with a refractory material; ii aninner wall within the first chamber forming a second chamber, whereinthe inner wall has a second air intake for flowing heated air at atemperature above the test temperature to the second chamber; iii a tubedisposed within the second chamber; iv a first air intake for providingpressurized air at a temperature below a test temperature connected to atube; v an exhaust port disposed through the housing in communicationwith the first chamber; vi a controller in communication with a firstthermocouple adjacent the second air intake for monitoring heated airtemperature at the second air intake and in communication with a secondthermocouple adjacent at the test specimen; and ix a closable opening inthe housing for allowing the at least one test specimen to be placed inthe first chamber; d. heating air forming heated air using a burnerburning a fuel, wherein the burner is in communication with a blowerproviding a variable flow of the heated air to the second air intake; e.forming pressurized air with an air compressor; f. mixing thepressurized air with at least one abrading media using an air gun andflowing the blended air to a tube passing through the first air intakeand further wherein the abrading media is disposed above an abradingmedia intake port of the air gun; g. mixing blended air from the tubewith the heated air from the second air intake forming mixed air at thetest temperature for impacting with the test specimen for a specificduration of time; and h. removing the test specimen from the furnace andweigh the test specimen and determine weight loss using a known densityto determine a volume of loss of the test specimen.
 2. The method ofclaim 1, further wherein at least 2 test specimens to 20 test specimensare disposed in the first chamber for testing sequentially.
 3. Themethod of claim 1 wherein a first test specimen is impacted by a firstabrading media and a second test specimen is impacted by a secondabrading media and the first and second abrading medias are different.4. The method of claim 1, further comprising the step of acceleratingthe velocity of the pressurized air through the tube.
 5. The method ofclaim 1, further comprising blending the pressurized air with theabrading media using the air gun, a meter connected to a pole, a funnelsecured to the pole aligned with the meter, and wherein the air guncomprises a body with an abrading media intake port for communicatingfrom the funnel to a mixing chamber in the body, an air nozzle securedto the body for flowing the pressurized air into the mixing chamber, andan air outlet for flowing pressurized air mixed with abrading media outof the air gun as blended air.
 6. The method of claim 1, furthercomprising using a third thermocouple connected to the controller formeasuring temperature within the first chamber.
 7. The method of claim1, wherein the controller comprises a processor in communication with adata storage, a display in communication with the processor, computerinstructions in data storage for instructing the processor to monitortemperature signals from the first and second thermocouples, compare thetemperature signals to a predetermined limit in data storage and controla valve that restricts flow of a fuel into the burner.
 8. The method ofclaim 1, wherein the refractory materials are either a ceramic, aninsulating material capable of a low thermal conductivity orcombinations thereof.
 9. The method of claim 1, wherein the testtemperature is between 230 degrees Fahrenheit to 2000 degreesFahrenheit.
 10. The method of claim 1, wherein the refractory materiallining the first chamber has a thickness ranging from 2 inches to 8inches.
 11. The method of claim 1, wherein the abrading media is aflowable particulate having a diameter between ⅛^(th) inches to 20microns.
 12. The method of claim 1, wherein the method is a one passtest method.
 13. The method of claim 1, further comprising monitoringpressure of pressurized air from the compressor with a pressurized airgauge and regulating flow of pressurized air with a regulator forcontrolling flow of pressurized air.
 14. The method of claim 1, furthercomprising monitoring negative pressure caused by the relation of thetube to the air nozzle of the air gun using a pressure gauge formonitoring negative pressure.
 15. The method of claim 1, furthercomprising controlling operation of the insulated furnace using an overtemperature controller connected to the controller when temperatures inthe insulated furnace exceed a predetermined limit.
 16. The method ofclaim 1, further comprising controlling air flow through the exhaustport using an exhaust valve disposed over the exhaust port.